This ball is a 1975-76 Spalding OAL MacPhail baseball. How much does this older style ball increase the value over a Bobby Brown or newer Rawlings MacPhail? I realize this is in part subjective but I'd think it would add desireability and value, I'm just not sure how much??
I believe having the Mantle on a MacPhail ball slightly increases the value, but it still is not from his playing days. That is why the price of Cronin-signed Mantle's commands a premium.
It doesn't significantly increase the demand, though it does increase the value. Basically, less people would be willing to pay slightly more for a MacPhail Spalding. One of those cases where you can get a premium if you have no real need to sell and can market it properly. Since proper marketing (not just parking an ad on eBay) costs money, the potential increase in selling price usually doesn't justify the higher associated marketing costs.
Basically, the ball might be worth $50-$100 more than a Rawlings ball, but it would cost you $50-$100 over time to market the ball to unlock that value.